Description: The concept of using nuclear bombs (units) to propel spacecraft was first invented by Cornelius Everet and Stanlislaw Ulam in 1945. The Units are projected rearwards of the vehicle and the explosive produces are subtended to some angle by the rear pusher plate. This transfers the momentum via a series of shock absorbers. In the 1960s Ted Taylor, Freeman Dyson and others worked on an actual vehicle design for this concept called Project Orion funded by various bodies at different stages including the US Air Force and General Atomic. After the project was cancelled Dyson developed an interstellar version which had a wet mass of 400,000 tons, made of of 300,000 units at 1 ton each. The Interstellar Orion would reach 10,000 km/s or 3.3% of light speed and reach the nearest stars in around 150 years. The technology associated with Project Orion is one of the few concepts we could actually have built yesterday, should the need error arose such as an Earth wide threat from a Near Earth Asteroid, although its fuel sources is politically sensitive.
Members: Ted Taylor, Freeman Dyson.
Dyson, F, Death of a Project, Science, 149, 3680, pp.141-149, 9 July 1965.